1. Field of the Invention
Embodiments of the invention relate to performing storage operations in a virtual environment and, in particular, to performing backup operations of one or more virtual machines.
2. Description of the Related Art
Many companies take advantage of virtualization solutions to consolidate several specialized physical servers and workstations into fewer servers running virtual machines. Each virtual machine can be configured with its own set of virtual hardware (e.g., processor, memory, ports, and the like) such that specialized services that each of the previous physical machines performed can be run in their native operating system. In particular, a virtualization layer, or hypervisor, allocates the computing resources of one or more host servers into one or more virtual machines and further provides for isolation between such virtual machines. In such a manner, the virtual machine is a representation of a physical machine by software.
Associated with each virtual machine is at least one virtual machine disk that is located in one or more files in a datastore. The virtual machine disk can be copied, moved, backed up, or the like, similar to a general data file. However, when a virtual machine is powered on, or executing on the host computer, the virtual machine disk is generally locked against access from outside the virtual machine. As a result, to perform a full backup of a virtual machine disk, certain conventional backup systems and methods require powering down the virtual machine prior to performing the backup operation.
To avoid the costly downtime in powering down a virtual machine, certain systems perform backup operations from inside the guest operating system of the virtual machine. This approach, however, also has significant drawbacks in that such backup copies, being performed from within the guest operating system, cannot capture a backup of the entire virtual machine.